Hey guys, I just ran the self test on my 91 F150 XLT 5.0 Auto. I got a code 53 on both the KOEO, and KOER. Which if I'm not mistaken is TPS Circuit Above max 4.5 Volts. What is the TPS, and where is it located. I also got a code 84, and 33 on the KOEO, and a code 98 on KOER. Any help would be greatly appreciated. I did remove and clean the IAC yesterday, which seemed to help quite a bit.

 

Ford Fuel Injection Throttle Position Sensor (TPS) Some info on the TPS and how to check it.

 

Code 33 is EGR valve not opening.
KOER 98 is hard fault present...I just had to chase one of those down on my truck. Your TPS is the Throttle Position Sensor, and it is located on the throttle body. It his a 3 wire connector going into it.

Mine was throwing code 22 (MAP Sensor) and 98 (Hard Fault). I had already replaced the MAP sensor for an earlier 22, and they go out very infrequently. TPS sensors rarely fail, so with both the 53 and 98 I would check the connector on the TPS, and follow the harness back from there looking for a short. You could also just try unplugging the TPS and moving that part of the harness around in different positions and running the self test multiple times to see if the 98 clears.

 

Thanks for your help. I will try that and let you know how that goes.